Systematics

Nabalus accommodates species in E Asia and North America (see Sennikov 2000), which were often placed in Prenanthes but are entirely unrelated to the latter (Kilian & al. 2009; Zhang & al. 2011; Schilling & al. 2015). The genus is, however, not monophyletic in its current circumscription (Zhang & al. 2011; Kilian & al. 2017). Instead two different lineages of the Dubyaea-Nabalus-Soroseris-Syncalathium clade of the Crepidinae (Zhang & al. 2011) have migrated into North America. One diversified into the eastern to southeastern true Nabalus (Schilling & al. 2015) including N. trifoliolatus, which provides the type of the generic name. The other is represented by the northwestern species pair N. sagittatus and N. alatus. The phylogeny of the Dubyaea-Nabalus-Soroseris-Syncalathium clade is, however, still unresolved. B,C,D,E,F